Global Oceans [in “State of the Climate in 2020”]

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Johnson, Gregory C.
Lumpkin, Rick
Alin, Simone R.
Amaya, Dillon J.
Baringer, Molly O.
Boyer, Tim
Brandt, Peter
Carter, Brendan
Cetinić, Ivona
Chambers, Don P.
Cheng, Lijing
Collins, Andrew U.
Cosca, Cathy
Domingues, Ricardo
Dong, Shenfu
Feely, Richard A.
Frajka-Williams, Eleanor E.
Franz, Bryan A.
Gilson, John
Goni, Gustavo J.
Hamlington, Benjamin D.
Herrford, Josefine
Hu, Zeng-Zhen
Huang, Boyin
Ishii, Masayoshi
Jevrejeva, Svetlana
Kennedy, John J.
Kersalé, Marion
Killick, Rachel E.
Landschützer, Peter
Lankhorst, Matthias
Leuliette, Eric
Locarnini, Ricardo
Lyman, John
Marra, John F.
Meinen, Christopher S.
Merrifield, Mark
Mitchum, Gary
Moat, Bengamin I.
Nerem, R. Steven
Perez, Renellys
Purkey, Sarah G.
Reagan, James
Sanchez-Franks, Alejandra
Scannell, Hillary A.
Schmid, Claudia
Scott, Joel P.
Siegel, David A.
Smeed, David A.
Stackhouse, Paul W.
Sweet, William V.
Thompson, Philip R.
Trinanes, Joaquin
Volkov, Denis L.
Wanninkhof, Rik
Weller, Robert A.
Wen, Caihong
Westberry, Toby K.
Widlansky, Matthew J.
Wilber, Anne C.
Yu, Lisan
Zhang, Huai-Min
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This chapter details 2020 global patterns in select observed oceanic physical, chemical, and biological variables relative to long-term climatologies, their differences between 2020 and 2019, and puts 2020 observations in the context of the historical record. In this overview we address a few of the highlights, first in haiku, then paragraph form: La Niña arrives, shifts winds, rain, heat, salt, carbon: Pacific—beyond. Global ocean conditions in 2020 reflected a transition from an El Niño in 2018–19 to a La Niña in late 2020. Pacific trade winds strengthened in 2020 relative to 2019, driving anomalously westward Pacific equatorial surface currents. Sea surface temperatures (SSTs), upper ocean heat content, and sea surface height all fell in the eastern tropical Pacific and rose in the western tropical Pacific. Efflux of carbon dioxide from ocean to atmosphere was larger than average across much of the equatorial Pacific, and both chlorophyll-a and phytoplankton carbon concentrations were elevated across the tropical Pacific. Less rain fell and more water evaporated in the western equatorial Pacific, consonant with increased sea surface salinity (SSS) there. SSS may also have increased as a result of anomalously westward surface currents advecting salty water from the east. El Niño–Southern Oscillation conditions have global ramifications that reverberate throughout the report.
Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 102(8), (2021): S143–S198,
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Johnson, G. C., Lurnpkin, R., Alin, S. R., Amaya, D. J., Baringer, M. O., Boyer, T., Brandt, P., Carter, B. R., Cetinic, I., Chambers, D. P., Cheng, L., Collins, A. U., Cosca, C., Domingues, R., Dong, S., Feely, R. A., Frajka-Williams, E., Franz, B. A., Gilson, J., Goni, G., Hamlington, B. D., Herrford, J., Hu, Z. Z., Huang, B., Ishii, M., Jevrejeva, S., Kennedy, J. J., Kersalé, M., Killick, R. E., Landschützer, P., Lankhorst, M., Leuliette, E., Locarnini, R., Lyman, J. M., Marra, J. J., Meinen, C. S., Merrifield, M. A., Mitchum, G. T., Moat, B. I., Nerem, R. S., Perez, R. C., Purkey, S. G., Reagan, J., Sanchez-Franks, A., Scannell, H. A., Schmid, C., Scott, J. P., Siegel, D. A., Smeed, D. A., Stackhouse, P. W., Sweet, W., Thompson, P. R., Triñanes, J. A., Volkov, D. L., Wanninkhof, R., Weller, R. A., Wen, C., Westberry, T. K., Widlansky, M. J., Wilber, A. C., Yu, L., & Zhang, H.-M. (2021). Global Oceans [in “State of the Climate in 2020”]. Bulletin of the American Meteorological Society, 102(8), S143–S198.
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